This invention relates to a photographic printing system in which picture information of an original film such as a negative film is subjected to light measurement and is then divided into picture element information and stored into a memory. The picture information are displayed on a monitor after the correction of the picture or density and color thereof and are then printed with a constant density of the main object to be photographed designated by an external means.
FIG. 1 shows a schematic diagramatic view of a system in which a picture information detecting device 10 is assembled into a conventional photographic printing apparatus to thereby divide the picture information of the original film such as a negative film and to store the divided picture elements. A negative film 2 delivered to a printing portion along a negative film carrier 1 are lit by a light source 4 through three complementary color (yellow Y, magenta M and cyan C) filters 3 and three primary color (blue B, green G and red R) filters 9 which are alternatively inserted into the filters 3 for collecting the picture information. The transmitted light through the filters 3 reaches a photographic paper 7 through a lens unit 5 and a black shutter 6. The photographic paper 7 is wound around a supply reel 7A and wound up around a take-up reel 7B in synchronism with the delivery and stoppage of the negative film 2 and photo sensors 8, such as photodiodes, for detecting picture density information of the three primary colors of blue, green and red are arranged near the lens unit 5 of the negative film 2. The photographic printing process in a prior technique is carried out by a detected signal from the photo sensors 8. The picture information detecting device 10 is disposed near the negative film 2 in an inclined manner with respect to the light axis LS of the light source 4 and the negative film 2, and, in front of a two-dimensional image sensor 11, a lens unit 12 is arranged for focussing the transmitted light through sustantially the central portions of the filters 9 and 3 and the negative film 2. A substrate 13 for setting processing circuits consisting of integrated circuits and so on for processing the picture is mounted on the rear surface of the unitted detecting apparatus.
The two-dimensional image sensor 11 comprises, as shown in FIG. 2, an image pick-up portion 11A for optically picking up the picture, a storage portion 11B for storing charges transferred from the pick-up portion 11A, and an output register 11C for outputting the charge stored in the storage portion 11B. The two-dimensional image sensor 11 of the construction described above operates to perform photo-electric conversion of the picture information of the two-dimensional area by controlling the drive signals SA to SC from a drive circuit, not shown, so as to thereby output an analog-type picture signal PS from the output register 11C. FIG. 3 shows one example of a circuit construction to be mounted on the substrate 13, and referring to FIG. 3, the image sensor 11 is operated by the drive signals SA to SC from a drive circuit 20. The light irradiated on the image pick-up portion 11A of the image sensor 11 is outputted as a picture signal PS from the output register 11C and is then sampled and held in a sample-and-hold circuit 21 with a predetermined sampling interval. The thus obtained value is converted into a digital signal DS by A/D (analog-to-digital) converter 22. The digital signal DS from the A/D converter 22 is inputted into a logarithmic circuit 23 to effect the logarthmic conversion of the digital signal DS, and after the conversion into a density signal DN, the density signal DN is writen into a memory 25 through a write control circuit 24.
According to the circuit construction of the type described above, when it is necessary to perform a normal printing operation, the filters 9 are offset from the light axis LS as shown in FIG. 1, and the transmitted light of the negative film 2 delivered and carried on the printing portion is detected by the photo sensors 8. The filters 3 are adjusted in accordance with the picture signals regarding the primary colors of B, G and R, respectively and the black shutter 6 is opened to expose the light on the photographic paper 7 with the predetermined exposure amount.
When it is necessary to detect the picture information of the picture elements and store them, respectively, the filters 3 are offset from the light axis LS as shown in FIG. 4, the respective filters 9 of the colors B, G and R are alternatively inserted across the light path from the light source 4 so as to thereby transmit the B, G and R light in the white light from the light source 4 to project them on the negative film 2, whereby the picture information of the yellow, magenta and cyan layers corresponding to the B, G and R colors, respectively are inputted into the image sensor 11. Since the two-dimensional image sensor 11 receives the transmitted light, through the lens system 12, of the negative film 2 carried on the printing portion by applying the predetermined drive signals SA to SC from the drive circuit 20 to the image sensor 11, the image sensor 11 divides the entire surface of the picture of the negative film 2 into a number of ordered small picture elements 2A and scan all of the picture elements of the negative film 2 subsequently according to the scanning line SL as shown in FIG. 5A. After the completion of the scanning operation, the picture signals PS are sequentially outputted from the output register 11C of the image sensor 11, and the picture PS signals are then sampled and held by the sample-and-hold circuit 21, so as to thereby convert the sampled value to the digital signal DS by the A/D converter 22. The digital signals DS from the A/D converter 22 are logarithmically converted by the logarithmic converting circuit 23 to obtain the density signals DN, which are then stored into the memory 25 with the arrangement corresponding to the picture elements 2A shown in FIG. 5B and with the density digital values of the negative film 2 by the control of the write control circuit 24. Furthermore, even if the picture information detecting device 10 with an inclined light axis is attached to a generally used photographic printing apparatus, a correct image with no deformation of the negative film 2 can be formed on the two-dimensional image sensor 11 because the light receiving surface of the image sensor 11 is in parallel with the negative film 2. This fact applies "camera adjustments" in a photographing technique, in which in order to simplify the mechanism of the printing device, the printing device is intentionally constructed so that the light axes of a lens unit for the two-dimensional image sensor 11 do not intersect with each other at substantially the central portion of the picture surface and the picture information can correctly be detected. After the digital values of the respective picture elements of the negative film 2 or the density values of the picture elements regarding the respective three primary colors have been stored in the memory 25, the digital values of the respective picture elements of the negative film 2 can be read out from the memory 25 for practical use. Accordingly, if the density values shown in FIG. 5B with respect to the three primary colors of blue, green and red have preliminarily been stored in the memory, the stored density values can be utilized as values for determining the exposure amount or correction amount in a photographic printing operation by optionally reading out the stored values and processing the operation thereof and the like. In addition, since the picture information detecting device 10 is constructed so as to detect the picture information of the picture elements of the entire picture surface, the precise and correct picture information detection can be performed.
In a photographic printing system of the type mentioned above, the picture information of an original film such as a negative film can be stored by dividing the picture into a numerous number of picture elements, so that the precise and correct information can be obtained as photographic picture information, and in addition, it is possible to precisely decide the exposure amount or correction amount for the photographic printing process from the thus obtained information. However, an actually printed result can be obtained only by performing the actual printing operation even if the exposure amount or the correction amount were thus decided, so that if the actually printed photograph is insufficient, the printing operation will have to be performed again.
In another aspect, with a photographic printing system aiming at processing a large number of negative films in a concentrated manner, the original film to be printed as shown in FIG. 6 is preliminarily examined by an inspection device 100. In this inspection, when it is determined that the printing amount obtained by a large area transmittance density (LATD) should be corrected, correction data is written in a paper tape 102 by operating the density key of a keyboard 101 and the data on the paper 102 is given to a photographic printing apparatus 200 to correct the exposure amount, thus carrying out properly the photographic printing operation. In actual printing operation, however, the correction operation by means of the keyboard is 101 considerably difficult for an operator with less experience and may include miss-determination. This is based on the fact that the correction amount is determined by the operator by the determination of the area balance between the density of the main object of the image on the original film and the background thereof.